So what do I have to add? Well, I wrote the "Deep Read" essay for the Globe and Mail's Books section over the weekend, focusing on Epstein's book. I agree with Amby that the book is pretty much compulsory for anyone interested in the science of sport. It's a great read and covers a lot of ground. In my essay, I also tried to place it in the context of current popular science writing, which favors coherent narratives and unambiguous answers -- the kind of thing that Jonah Lehrer did so well. To me, the strongest (and bravest) element of Epstein's book is that he resisted the urge to streamline the evidence. He does the reader the courtesy of assuming that we're capable of handling some complexity and ambiguity, and the book is richer for it.

I also wanted to highlight the answer he gave the final question in his RW Q&A session, which was about what distance runners should take away from the book:

I would say to any distance runner: If you train with a partner and you're not getting the same results out of it as he or she is, the problem is very likely you in the deepest sense of the word. It's probably your genetics, and you should try something different. I was often afraid to try different training methods. You get into a groove, and you don't really want to change things, and distance runners are creatures of habit.

Now, I'm not suggesting that we should take this advice too far. Sometimes people will get differing results from the same training even if the training is optimal for both of them -- that's another aspect of genetic variability. But I do think Epstein's point is important, and we should bear it in mind before getting sucked into the rabbit hole of debating exactly how much mileage a marathoner should run, and how much of that should be at what specific fraction of marathon pace, and so on. Unless you're training an army of mutant clones, there's no single "right" training program. The big principles -- stress, recovery, adaptation -- are universal, but specific workouts aren't.

The best counterexample to the most powerful popular science narrative of the past decade is a tomato-faced Finn who lives in a tiny hamlet north of the Arctic Circle. Eero Mantyranta was born with a single misspelling – an adenine molecule instead of a guanine – in a 7,138-unit-long stretch of DNA associated with red-blood-cell production. As a result, he has a distinctly reddish-purple complexion, up to 65 per cent more hemoglobin to carry oxygen from his lungs to his muscles than the average person, and seven Olympic medals in cross-country skiing.

At least, that’s one way of telling his story.

The other way, as author David Epstein finds out when he makes the long trek to Lapland to track down Mantyranta, more than 40 years after his last Olympic triumph, is to focus on his childhood – so poor that his whole family shared a single fork, skiing on wooden planks by the time he could walk, an hour each way to school across a frozen lake – and on his gruelling training regimen as a teenager, when he realized that success as a skier could save him from a life of hard labour and deadening poverty.

So which is it? That, in essence, is the question that Epstein, a senior writer at Sports Illustrated who specializes in sports science, wrestles with in various guises throughout The Sports Gene: Inside the Science of Extraordinary Athletic Performance. The current conventions of popular science writing dictate that he should settle on a single counterintuitive but easily digested answer, preferably one that, if applied to your own life, will help you improve your jump shot and get that promotion at work you’ve been hoping for.

Instead, Epstein eventually concludes that the secret of Mantyranta’s success is “100 per cent nature and 100 per cent nurture” – an equivocal answer that surely made his literary agent blanch, but should earn cheers from the rest of us... [READ ON]